put a hydrogen train on a narrow track

Stadler and ARST have presented in Erlen (Switzerland) what both companies describe as the first hydrogen train designed specifically to run on narrow gauge tracks. The idea is that the convoy will begin transporting passengers in 2028 on three lines in northern Sardinia. Below these lines we tell you all the information.

What has happened? The Swiss manufacturer and ARST have closed a project that started with a framework agreement signed in 2023 and that contemplates the supply of ten hydrogen trains for the Sardinian network. According to the press release, these vehicles will replace the current diesel units and will allow, according to the company, to save more than 2,100 tons of CO₂ per year, a figure that Stadler compare with avoiding about 450 car trips around the planet.

Why is it a technical novelty? Until now, the hydrogen trains that circulate in Europe, like Alstom’s Coradia iLint in Lower Saxony or Siemens’ Mireo Plus H in Bavaria, have been developed for the standard gauge gauge of 1,435 millimeters. Sardinia, Calabria and Sicily, on the other hand, preserve a network inherited from the 19th century with a width of only 950 millimeters, which imposes much stricter axle load limits. Stadler had to design a completely new lightweight aluminum body to fit into that tight space.

It is worth clarifying, however, that this is not the first time that something similar has been proposed. And just as they point From Trenvista, in 2011 the Spanish operator FEVE converted a retired 3400 series unit, the so-called Fabiolo, to hydrogen, although that project was later abandoned. What is certain is that it is the first narrow gauge hydrogen train conceived from the beginning to enter commercial service.

In detail. The propulsion system is based on fuel cells and hydrogen tanks, but with a peculiarity, because instead of distributing the components across the roof of the train, as other manufacturers do, Stadler has concentrated all the equipment in a central car, named Power Pack.

This module acts as a kind of rolling charger that transforms hydrogen into electricity to power the traction batteries, freeing up space in passenger cars for air conditioning, panoramic windows and access to the lower floor for people with reduced mobility.

With its own hydrogen. Most hydrogen trains in service are refueled at conventional stations. ARST has opted for a model designed to produce its own hydrogen through electrolysis powered 100% by solar energy, integrating the production plant within the transport network itself. As explained by Carlo Poledrini, central director of ARST, in Stadler’s notethese vehicles are “a central element of the decarbonization strategy of the narrow gauge network” and represent “the first step in the evolution of ARST from a transport operator to an energy company capable of powering its own service network.”

Expansion. The project is part of a broader initiative by the Italian Government and its Ministry of Infrastructure and Transport to decarbonise the narrow gauge lines in the south of the country. Stadler affirms which already builds nine similar trains for Ferrovie della Calabria and two more units for Ferrovia Circumetnea, in Sicily, the latter adapted for the slopes around Etna.

And now what. Before receiving passengers, the ten Sardinian trains must complete a battery of safety and operational tests. If everything progresses as planned, the first unit should be circulating with travelers in 2028, and from there we will see if the idea ends up gaining traction.

Cover image | Stadler

In Xataka | Switzerland installed the first railway solar plant in the world: a year later, it has been such a success that its neighbors are already asking about it